JSFiddle - React, Tailwind, and code Playground

HTML

<div id='dad'>
    <span></span>
    <div class='b'>Hello World!<br/>World</div>
</div>

CSS

div#dad{
    border:solid;
    height:300px;
    width:300px;
    text-align:center
}
span{ 
    line-height:300px; 
}
div.b{
    vertical-align:middle; 
    display:inline-block; 
    background-color:yellow;
}